Anonymous has launched a massive attack on government and pro-SOPA/PIPA websites today in retaliation for a federal raid on Megaupload earlier today. The AnonOps Twitter account claimed responsibility for the attacks, which are being promoted with the #OpMegaUpload hashtag. As of press time, the websites of the Motion Picture Association of America (MPAA), the Recording Industry Association of America (RIAA), the Justice Department and Universal Music Group have all been taken online. As this article was being written, the U.S. Copyright Office was forced offline as well.

The loosely organized hacktivist collective began recruiting sympathizers for the attack earlier this afternoon on IRC as news of the Megaupload raid got out. Tweets were also put online claiming that Anonymous was attempting to take down whitehouse.gov; however, the site was accessible (though extremely slow) as of press time.

A Twitter account associated with Anonymous, @youranonnews, also reports that “FBI.gov is next to go down.”

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